The 2006 Kythira (Greece), Mw6.7 slab-pull event: tectonic implications and the geometry of the hellenic wadati-benioff zone

• Main Authors: F. Vallianatos, E. Papadimitriou, I. Nikolintaga, V. Karakostas
• Format: Article
• Language: English
• Published: Istituto Nazionale di Geofisica e Vulcanologia (INGV) 2008-06-01
• Series: Annals of Geophysics
• Subjects: Hellenic Arc; subduction zone geometry; slab-pull event
• Online Access: http://www.annalsofgeophysics.eu/index.php/annals/article/view/3016
• ISSN: 1593-5213; 2037-416X

A strong (Mw=6.7) intermediate depth earthquake occurred on 8 January 2006 (11:34 UTC) in southwestern
 Aegean Sea (Greece) causing limited damage to structures on the nearby islands of Kythira and Antikythira, as
 well as western Crete Island. The epicentral area belongs to the SW segment of the Hellenic Arc, which is known
 to be associated with the occurrence of large shallow and intermediate depth earthquakes, mainly due to the
 subduction of the Eastern Mediterranean oceanic lithosphere under the Aegean microplate. The main shock occurred
 on a dextral strike slip fault at a depth of 75 km, within the descending slab, as it is revealed by both, the
 spatial distribution of the accurately located aftershocks and its fault plane solution determined in the present
 study and implying a slab-pull event. The aftershock activity from 8 to 31 January 2006 is distributed in depths
 ranging from 55 to 75 km, and being comprised in an almost rectangular and vertical plane with a length equal
 to 28 km and a width of 20 km, which adequately defines the dimensions of the rupture area. The geometry of
 the Wadati-Benioff zone in this area, namely the southwestern part of the Hellenic Arc, is explored by an exhaustive
 analysis of all the available phase arrivals gathered from the International Seismological Centre, and the
 relocation of the earthquakes occurred since 1964 in the South-West Aegean region.